Personally, I'd say if she wants the car then she can buy the car. Then if the worst happens and you two go your separate ways, there won't be car custody battles/you won't get saddled with trying to get rid of it, etc, and there won't be any bad feelings about "Well it's MY car, I'm paying for it, but she drives it all the time," yadda yadda yadda.

To your question: It's not a cargo hauler, but I've had the same car for 12 years and it's still running great - a 1994 Nissan Sentra 4-door. It's always been <$1000 to fix (even when I was involved in a smash up on the highway and the other driver fled the scene) and it still runs great. The only recurrent issues are electrical, but the batteries are cheap, and I'm sure I'm not helping things by driving it once or twice a month.